There are a number of events that take place within War Rock that provide exclusive prizes and boosts for performing certain actions while playing. Events can be accessed directly through the War Rock client, and are added/rotated frequently. Some examples of current/past events include:

Marble Event:
Roll the dice and get assigned a random mission to complete for rewards.
Halloween Event:
Kill enemies and win matches to find/earn Candy pieces that can be exchanged for rewards.
Christmas Event:
Complete the ‘Ten Days of Challenges’ to win prizes.
Khali Kill Event:
Work with your team to surpass a set kill count on certain maps to win prizes.
Chatting Box Event:
Each 30-minute period of active game time (not in the game menus) awards coupons that can be exchanged for rewards.